Treehugger design and green architecture contributor writes: "The phrase "net-zero" energy or "zero-carbon" has always troubled me. I have noted that I can make my tent net-zero energy if I have enough money for solar panels, but that's not necessarily a sustainable model. Others have been troubled by the concept as well; Passive House consultant Bronwyn Barry writes in the NYPH blog: 'I'm betting that our currently mythical 'Net Zero Energy Homes' – however one defines that empty integer – will be buried in a marketing graveyard somewhere." more